Counterbalanced unwatering apparatus



Dec. 13, 1960 M. MACHOL ETAL COUNTERBALANCED UNWATERING APPARATUS 4Sheets-Sheet 1 Filed Feb. 20, 1959 ii -il INVENTORS at, MR. MA

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Dec. 13, 1960 M. R. MACHOL ET AL COUNTERBALANCED UNWATERING APPARATUS 4Sheets-Sheet 2 Filed Feb. 20, 1959 INVENTORS C A RaAMs &, M. R MAcHo\.

g r MMI-EJZUL ow E n Dec. 13, 1960 M. R. MACHOL ET AL 2,963,370

COUNTERBALANCED UNWATERING APPARATUS Filed Feb. 20, 1959 4 Sheets-Sheet5 Pie. 6.

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INVENTORS CA. REAMS ATTORNEYS MACHOL.

Dec. 13, 1960 M. R. MACHOL ETAL 2,963,870

COUNTERBALANCED UNWATERING APPARATUS Filed Feb. 20, 1959 4 Sheets-Sheet4 Q #2 I Q m m m m Zo F x i 3% l; :l/ g;f

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INVENTORS C.R.REAMS @MRMACHOL BY WM ATTORNEYS United States PatentCOUNTERBALAN CED UNWATERING APPARATUS Morris R. Machol, New York, N.Y.(1819 G St. N.W., Washington 6, D.C.), and Clinton A. Reams, 192i? 8 St.N.W., Washington, D. C.

Filed Feb. 20, 1959, Ser. No. 794,766

12 Claims. (Cl. 61-65) This application is a continuation-in-part ofapplicants copending application Serial No. 324,778, filed December 8,1952, and now abandoned.

This invention relates to hydraulic means for elevating and loweringheavy bodies, particularly floating objects such as vessels and barges,to remove the object from the water and place it upon a cradle or othersupport which may be provided with one or more wheeled trucks to enableit to be moved with its load over the land.

There are four well known means for lifting a vessel or other floatingobject out of the water in order to examine or work on its underwaterbody, including graving docks (usually called dry docks), floating drydocks, marine railways and vertical hoists. Each of these is suitablefor certain conditions but all four are extremely expensive to build andto operate. Each requires large quantities of power which is only used asmall part of the time (this being one reason for the costly operation);and each of the first three are slow of operation. The vertical hoist,which has been used only in small capacities, is faster by virtue ofusing proportionately larger amounts of power.

The purpose of this invention is to provide means for unwateringfloating objects which will cost much less to build than theconventional means, which will require a minimum of mechanical effort,will need little or no power from an outside source (stream or electric)and will require only a small fraction of the operating and maintenancecosts of the conventional types and which will raise the vessel in avery short time. By unwatering is means removing floating objects fromthe water and supporting them otherwise.

This invention is a combination of well known and thoroughly testedprinciples of mechanics which produces an unwatering facility that costsmuch less to build, costs very much less to operate, requires a minimumof mechanical effort, and will operate in a fraction of the time neededfor the conventional methods.

The simple principle on which this invention depends is that water froman elevated tank, which can either be filled by a hydraulic ram or smallpump or from a public water supply system, is used so that its weightwill counterbalance the weight of the vessel.

A preferred embodiment of the invention is shown in the accompanyingdrawings, wherein Figure 1 is a side elevation and Figure 2 is a planview of the device showing the lifting platform raised from the waterand the counterweight tank in lowered position. These figures also showin dotted lines the platform lowered beneath the water to receive ordischarge a vessel or other floating object, the counterweight tankbeing likewise shown in elevated position.

Figures 3 and 4 are respectively a plan and side elevation of thecontrol device for the power motor and valves which control the flow ofwater into and out of the counterweight tank.

Figure 5 is a side elevation of the platform stop and tipping means.

Figure 6 is a schematic plan view showing an arrangement which utilizesour unwatering apparatus to position a plurality of ships in dry storageon the land.

Figure 7 is an end view of the arrangement of Fig. 6.

Figure 8 is a diagrammatic view similar to Fig. 2, showing an elongatedtank for use with large ships; and

Figure 9 is a diagrammatic elevational view looking toward the left sideof Fig. 8.

In the apparatus shown in the drawing, a lifting platform 10 is movablysupported by two or more pairs of columns 12, pivotally mounted at theirlower ends on fixed supports 14 carried by a suitable underwaterfoundation 16, and hinged to brackets 18 on the under side of thelifting platform, near the edges thereof, to cause the lifting platformto maintain a horizontal position when being raised from or lowered intothe water, as shown in Figure l. The vessel or other object 20 to belifted from the water is readily chocked up on the lifting platform whenfloating above it in alinement therewith by raising the platform andcradle 22 until the latter engages beneath the bottom of the floatingobject, as by pulling in on the pair of cables or chains 24 which aresecured by fastenings 28 to the two inner columns of two of the pairs ofsupporting columns 12 near their upper ends where they are pivoted tothe lifting platform.

The cables or chains 24 may be continuous and have their inhaul sectionspassing shorewards and connected to the counter-balancing and controlmeans and their outhaul sections 26 reeved around sheaves or sprockets30 rotatably supported on underwater pedestals on the water side of thelifting platform and around sheaves or sprockets 32, rotating on fixedjournal supports on the shore side of the lifting platform, as shown inFigures 1 and 2. Each inhaul section of the cables 24 passes over twospaced guide pulleys 34 and 36 between which is a slack take-up pulleyor sprocket 38 provided with a brake of any suitable type. Two guidepulleys 40 are provided on the land side of the lifting platform forsupporting each outhaul section 26 of the pair of cables 23 near whereit enters the water. The cables or chains 24 are actuated by means of acontrol cylinder 42 having a piston provided with a crosshead 44 towhich the inhaul and outhaul sections are connected at their shore endsby means of clamps 46 (see Fig. 3). A counterbalance cable 48 is alsoattached to the crosshead 44 for supporting the greater part of theweight of the platform and load as it is lifted or lowered.

The cylinder 42 may be operated in any desired way to supply the powerneeded to actuate the lifting cable's, but preferably water from theelevated tank 50 is used to act against the piston within said cylinderalthough water carried by the piston rod 84 under pressure from thelocal water supply system may be used for this purpose. Water fromeither source is admitted through pipe 52 to one end or the other of thecylinder through a four way valve 54 and the pipes 56, which are soarranged that when one is connected to the water supply 52 the other isopen to a drain pipe. The same water supply may also be used to fill theelevated water storage tank 50 or a special pump may serve this purpose.

Manual actuation of the valve 54 permits the speed of operation of thecylinder and lifting chains to be controlled to correspond to the timenecessary to fill or empty the counterbalancing tank 58 to which thefree or inshore end of the counterbalance cable 48 is attached afterpassing under the guide pulley 60 at the foot of the storage tank towerand the guide pulley 62 at the top of the tower beneath the storage tank50. A flexible pipe 64 leads from the bottom of the storage tank 50 tothe counterbalance tank 58 for filling the latter, a suitable '3 valveor valves 66 being provided for controlling the flow from the storagetank.

The counterweight tank 58 when empty and the platform 10 and columns 12in lowered position approximately balance each other. The vessel orother object 20 in its lower position is supported by the water in whichit finals Each inch it is raised reduces the bouyant effect of the waterand increases the weight or pressure on the platform. Water drainingfrom storage tank 50 into counterweight tank 58 increases the weight ofthe latter, and the counterweight tank on the one hand and the platformand its load while partially submerged on the other hand approximatelybalance each other and the vessel .comes out of the water just as fastas the water is released into the counterweight tank.

When the platform 14) is at its lowest position, the speed with whichthe ship rises is roughly half that of the movement of the chainconnection 24. As the platform approaches its upper position thevertical speed of the vessel becomes proportionately less until at thetop position it has no vertical movement. Therefore the pull on thechain, which may be increased'at first, must be thereafter reduced asthe vessel rises or the speed will become excessive as the platform hitsthe dock. This reduction of pull is accomplished in three ways; byclosing valves 66 from the store e tank; by releasing water for thecounterweight tank '53 through valves inits bottom; by turning valve 54to apply pressure on the end of hydraulic cylinder 42 and the side ofthe piston therein away from the platform; and by using the brakes attached to sprockets 38. The speed with which the vessel can be raised isonly limited by the size of the valves and the speed with which watercan be drained into and out-of counterweight tank58. When the platformis empty and the tank is empty, water pressure on the end of hydrauliccylinder 42 furthest from the platform, acting through the backhaulchains, will pull the platform down. Thus a ship resting on the platformcan be launched by the proper control of the amount of water incounterweight tank 58.

When the platform is in its top position, even the weight of a vesselexerts no horizontal thrust to rotate the columns outwards on theirlower axes, but as they move outwards the thrust increases as theplatform lowers and must be counteracted. Without a vessel, the weightof the platform will not balance the weight of the counterbalance tankuntil the platform has been moved some distance out and down. For thispurpose two hydraulic'cylinders 68 are provided, arranged as auxiliarypushers, their pistons being actuated 'by water from the tank towercontrolled by a valve. The pads 70 on the outer end of the pistonsengage the pads 72 on the platform for this purpose. also engage ordisengage locking pins 76 pivoted at 78 with lock plates 8% in themanner shown in Figure 5 to release the platform before moving it. Asthe platform The pads have earns 74 which moves out and down its weightbecomes effective to ballance that of the counterbalance tank and thechains 24 suifice to control its movement.

This invention has many advantages. The only power required to operatethe lifting platform is that to run a pump to supply sea water enough tokeep storage tank 50 filled in those places where a public water supplyis not available, or is too expensive.

Two, three, four or more pairs of columns 12 can be used for whateverlength of platform is desired; and the ship may be hauled out sidewise,or the bow of the ship can be pointed inshore lengthwise of the platformand lifted out of the water endwise. In either case where the drawingsshow only one pair of columns 12 there can be as many pairs of columnsextending out into the water or along a slip as are needed to supportthe length of platform desired.

The discharged water from the counterweight tank 58,

led to the area'of the platform foundations, will provide an outwardcurrent of water that will help to keep that area free from silt.

When a vessel or other floating object is resting in checks on theplatform in the water and is ready for the lift to begin, it exerts noweight on the platform, since it is afloat and entirely supported by thewater. The counterbalance tanks weight when empty equals and balancesthe weight of the platform and columns. If, at the start of the lift,the columns are at an angle of 60 with the horizontal, the chain 24 willmove two inches while the platform rises one inch; Therefore, for eachpounds additional weight onJ-the platform as the ship rises from thewater, only 50 pounds of water will be needed in the counterbalancetank.

If the cable 48 from this tank, instead of being fastened to thecrosshead as shown, is fastened at the lower sheave 60 and then reevedaround another sheave on the crosshead and from there over the lowersheave 60, the tank would move twice the distance that the crossheadmoves and only 25 pounds of water would balance 100 pounds ofship.

The smaller the angle of the supporting legs the greater the discrepancybetween the vertical distance travelled by the platform and the distance(not quite horizontal) travelled by the chain. If the chain moves twiceas fast as the platform rises vertically the strain on the chain is halthe weight of the ship. So it becomes desirable to keep. the angle assmall as possiblethe deeper the foundations for support of the pillarsthe less the angle of the pillars in the bottom position.

Two factors control this depthone the amount by which the depth of thewater exceeds the draft of the ship. If the hoists design intends thatit only be used during the upper half of the tide run-one half of thetotal tide will be added to the depth.

If it be assumed that the ship to be raised has a displacement of 5000tons, without cargo or fuel it might Weigh 3600 tons. Be it assumedfurther that the ratio of chain travel to vertical travel of theplatform is 2 to 1, a ratio which may easily be provided. Near the .topof its swing the vertical rise of the platform is very small inproportion to the movement of the chain, so that the ratio of the weightof the platform to the tension on the platform is very high. But whenthe platform is near its lower position, the ship is largely waterborne,and there is very little Weight on the platform. If the ship draws 24feet of water, when it is half out of water the weight on theplatformshould be in the neighborhoodof 2000 and the travel ratio of chain toplatform about 10 to 1. At that point the strain on the chain should benear its maximurn and would be about 200 tons. In other words, as theship rises, the increase in the proportion of its weight which must besupported from the chains is largely oifset by the mechanical advantageresulting in the increase of the ratio between the distance travelled bythe chain and the vertical rise of the platform.

As the platform rises, each one degree rotation of the columns givesalmost the same movement of the chain but each degree rotation of thecolumns gives less and less lift of the vvessel until when the columnsare vertical the lift is zero. As the ship is raised toward the top ofthe lift its weight rests entirely on the platform, but less and lessweight of Water is needed in the tank 58 to balance it because of thischange in angle. Thus in order to maintain a balance between the weightof the ship and the weight of the counterbalance tank 58, it isnecessary that during the first part of the lift water must flow intothe counterbalance tank to increase its Weight while during the latterpart of the lift water must drain from the counterbalance tank todecrease its weight.

To accomplish, this automatically the invention includes a tensionmeter, as illustrated in Figures 3 and 4. This comprises a flanged metalplate or disc 82 fixed on the end of the piston rod 84 which slidesthrough the crosshead 44. A housing or yoke 86 to which the wire cable48 is attached projects tom the crosshead 44 and contains a spring 88surrounding the piston rod between the disc 82 and the crosshead whichis under compression when the weight of the vessel on the platform isless than that of the counterbalance tank as shown in Figures 3 and 4. Aheavier compression spring S is arranged in the housing 86 between thedisc 32 and the fitting 92 into which the end of the wire rope 48 issecured by means of a swivel 94. These two springs 90 and 88 limit thetravel of the disc 82 in relation to the housing and crosshead 44 andtransmit the pressure on the piston to them and to the chains 24.Electric contacts 96 attached to the housing 86 are contacted by thedisc 82 at the two limits of its movement and act to open and close thevalves that permit flow of water into and out of the counterbalancetank. With the disc in its middle position neither contact is closed andall valves are closed. Thus the balance between the pull on the cabledue to the Weight of the counterbalance tank and the pull on the chainsdue to the weight of the ship on the platform is maintained and effectedautomatically within small limits determined by the tension of thesprings. If the tension of the heavier spring 90 is 50 pounds more thanthat of the lighter spring 88, then the imbalance (or unbalance) willnot exceed 100 pounds.

A drum 98 actuated by an electric motor 100 may be substituted for ormay augment the cylinder 42. With a 50 pound spring tension mentionedabove, the drum need only exert a pull of 101 pounds to raise or lower aship regardless of how many tons it weighs, and only a very smallelectric motor is needed. The speed with which the ship can be raisedand lowered is limited only by the size and number of valves controllingthe flow of water into and out of counterbalance tank.

A site may be selected which it not too far away from high ground onwhich there is a natural source of watera pond, lake, reservoir or evena stream. One obvious example would be the Hudson River running past thePalisades on the Jersey shore. In such a situation the upper tank ortanks 50 would be eliminated and replaced by the outlet end of a pipelaid from the water supply describedto discharge into the rectangulartrough. This would eliminate pumps and the power to drive them and alsoeliminate the time taken to pump water into the tanks.

When such a distant water source is available, the structure supportingthe rectangular trough may be built tall enough to allow a greatervertical travel of the trough. This could be made 100 feet and the totaltravel of the crosshead 44 could be made 20 feet. If the wire cable 48between the pulley 60 and the crosshead 44, is then reeved over a seriesof pulleys like a rope is reeved in a block and fall, the additional to1 reduction in speed will make the strain on cable 48 (and the weight ofwater needed in the tank) 40 tons, to balance a 5000 ton ship.

The embodiment of our invention thus far described comprises a platformthat will raise a small ship-one not over 75 or perhaps 100 feet inlength. A longer ship-perhaps 500 feet-would require a longer platformand a number of towers and tanks would be needed. But this would requireabsolute control of the rate of flow of water to insure that each tankwould fill or empty at exactly the same rate. This would be difficult ifnot impossible to accomplish. If the tank at one end filled faster orslower than the other end-one end of the platform would be further outand further down. This twisting strain might well wreck even a sturdyplatform and the ship on it.

We meet this situation by substituting one long rectangular trough forthe tank 58. This trough may be provided with transverse baflles 58a toprevent a sudden surge of water to any point which may temporarily beslightly lower than another. It can be filled either from a highertrough, from tanks or from an outside source of water. As many pistonand cylinder engines as desired may be provided, each connected bycables to both the platform supporting columns and to the counterweightsuspension means. To keep the rectangular tank moving evenly at bothends two shafts 101 will be run parallel to the length of the tank, oneabove and one below. On the end of each shaft is a sprocket with a chain102 engaging the upper and lower sprockets. The chains would be fastenedto the end of the tank at 103. There would be little or no strain on thechains since water in the trough would constantly seek its own level.

One of the shafts 101 may provide a convenient method of preventingexcessive speed, since a gear on one end thereof may be connectedthrough a suitable speed increasing gear train to a governor whichregulates the flow of water into and/or out of the tank 58, or othermeans for regulating the speed of movement of said tank.

A marine railway or dry dock can only handle one ship at a time and thefacility is tied up until repairs are completed which may be from a dayto many weeks.

The hoist herein described can be coupled to a transfer system andservice an entire fleet of ships, lifting each ship out of the water andmoving it to a prepared place on shore in a matter of minutes.

The platform 10 is then equipped with a set of transverse rails orhearing races -preferably bearing races, since bearings would requiremuch less weight than wheels. Resting on top of platform 10 is theplatform 111 on which the ship and its cradle rests. There are bearingraces 112 on the bottom of this platform and bearings 113 between thetwo sets of races in retainers or cages. Alongside the platform 10, inits top position, and running parallel to the center line of the ship isa set of rails 116. Another plat-form 117 is equipped with supportingaxles and wheels to run on the rails 116. On the top of the platform 117is another set of bearing races to match the bearing races on platform10. At various stations along the rails 116 are sets of rails 118running at right angles to rails 116. A wheeled platform 119 runs on thetransverse rails 118, and bearing races 121 on top of platform 119 matchthose on platform 10.

Between platform 119 and the rails 116 and between platform 117 andplatform 10 in its upper position there are stationary platforms 122 and124 respectively, equipped with bearing races 123 and 125.

Docking a ship proceeds as follows: After platform 10 is in its topposition and locked, the platform 111 and ship is rolled on bearings 113over platform 124 onto platform 117 utilizing an additional set of cagedbearings 126 and plat-form 117 is then moved on its wheels until it isalongside platform 119 in its prepared position. The ship supportingplatform 10 is then rolled on the bearings 126 onto platform 122 andthence by means of caged bearings 127 onto platform 119. Platform 117can then be rolled :back to pick up another ship and move it to any oneof several other prepared platforms similar to 119.

In this way the hoist can lift one ship after another and each can beeasily and quickly moved to a position on shore, where it may be storedout of the water'with no fouling of bottoms and no cluttering up of theWater or stream. Any work needed can be done on the underwater body ofthe ship in the dry.

We claim and desire to secure by Letters Patent the following andequivalent arrangements of deck, platform, columns and lifting means,with our control apparatus:

1. In an unwatering apparatus the combination with a stationary dock ofa vessel supporting platform movably mounted alongside said dock onspaced right columns pivoted at their bases to underwater supports andhinged at their upper ends to the underside of said platform, means forlowering and raising said platform into and out of the water whilemaintaining it horizontal by tilting said columns, an elevated watersource alongside said dock, a counterweight water tank and means formovably suspending it at a lower level than said water source, means fordischarging water from said storage tank into said counterweight tankand means for discharging water-'out of saidcounterweight-tank, controlmeans' for. said water discharging means, a connectionbetweenthezcounterweight tank suspending means and the platform loweringand raising means through which the weight-of'said counterweight water'tank and the water thereincounterbalance'thatof said platform anditsload, and means responsiveto' changes in the tension on saidconnection for operating the-water discharging control means to maintaina properbalance between said counterweight tank and'said platformduringlowering and raising of: the-latter. r

2. An unwatering apparatus 'assetforth in claim 1 wherein the means forlowering and raising the vessel supporting'platform includes a cylinderand piston engine, a, connection between said engine and platform, andmeans-for supplying fluid pressure to said cylinder on either side'ofthepiston to control the direction of movement of said platform.

3. An unwatering apparatus asset forth in claim 1 wherein theconnection'betweeu the counterweight tank suspending means and theplatform lowering and raising means includes a rotatable member, brakingmeans associated with said rotatable member, and control means foractuatingsaid braking means.

4. An: unwatering apparatus as set" forth in claim 1 whereinthe-platform raising and lowering means, the counterweight water tanksuspending means and the connectionbetween said raising andloweringand-suspending means include aflexible-cable and power meansassociatedwith said cablefor pulling it in either direction.

5. In a control device for a lifting platform as set forth in claim 1having a moving cable in the connection between said counterweight tanksand columns and a member reciprocating therewith, a reciprocating powermeans, a collar firmly affixed to the power means, spaced limit stopmembers moving with" the reciprocating member, these limit stop membersbeing positioned to limit the travel of'said collar withrespect to themoving cable, and an electric circuit including means actuated by saidtravel of the collar to control the valv'esallowing water to flowinto'and out of the counterbalancing tank;

6. A control device for a lifting platform asset forth in claim 1 havinga cable in the connectingmeansbetween the counterweight tank. audiplatform, a drum around which said cable passes, and anelectric motorconnected to the drum for controlling lifting and lowering movement ofsaid platform.

7. The combinationof a stationary dock and platform pivotally mounted onpairs of upright columns pivoted at-their bases for tilting away fromsaid dock, an elevated storage water tank, a counterweight tank andmeans movablysuspending it below saidstorage tank, flexible means forconnecting the tank suspending means with said columns for retainingsaid platform against saiddock and counterbalancing. said platform whentilted away from said dock, automatic. control, means for releasingwater from;'saidstorage. tank into: said counterweight tank and forreleasing water. from said counterweight tank for balancing the weightof a movable body on saidplatform when said platform is tilted, poweractuating means associated with said flexible connecting means foroperating it in either; direction of pull,.independeut control meansfor. saidpower actuatingmeans, a tension meter connected: between twocontiguous endsv of said flexible connecting means comprising a-linkconnected at one end to an end. of said flexible connecting means, aslide guided for movement withrespectto the free end of said link, saids-lide havingastop atone endand its other end connected-- to'the othercontiguous end of said flexible connectingmeans, spring'meansmountedinsaid-link and engaging said slideto position saidstop normally-betweenthe ends of saidlink, and contact-members mounted on said-link adjacentits ends imposition to be engaged by said slide uponsaid stopapproaching. either end-of said link under achange in the pull on saidflexible connecting means sufiicient to flex. said springs and causerelative movement of said'slide with respect to-said link.

8. The combination of a stationary dock and a platform pivotally mountedon pairs of upright columns pivoted attheir bases for tilting away fromsaid dock, an elevated storage water tank, a counterweight tank andmeans movably suspending it belows aid storage tank, flexible means forconnectingthe tank suspending means with said columns for retaining saidplatform against saiddock andcounterbalancing saidplatform when tiltedaway from saiddock, automatic control means for releasing water fromsaid storage tank into said counterweight tank and for releasing waterfrom. said counterweight tank for balancing the weight of a-movable bodyonsaid platform when saidplatform is tilted, power actuating meansassociated with said flexible connecting means for, operating itineither direction oflpull, independent-control means for said poweractuatingmeans, a piston and fluid pressure cylinder fixed to said dock,a thrust connection between said piston and flexible connecting meansadaptedto move the latterin either direction of pull, a member in; saidthrust connection having limited sliding move ment with respect to saidflexible connecting means, and means associated therewith operating atthe ends of said sliding movement for actuating said. automaticallycontrolled: water releasing means.

9; Apparatus-of the kind set forth in claim 1 wherein the connectionbetween the counterweight tank and platform comprises a flexible cable,a drum around which the cable passes, and an electric motor to operatethe apparatus through the drum.

10, Apparatus as claimed in claim 1 in which the suspension means forthe. counterweight water tank comprise two parallel rotatable shafts,mounted longitudinally of said tank,: one'above the uppermost and one.beiow the lowermost limits of its path of travel, sprocket wheels fixedto the'ends of each shaft, andza. chain at each end of the tankconnecting the sprocket wheels. on the upper shaft to those on thelowershaft and the adjacent end. of the counterweight tank.

11; Apparatus as claimed in claim 10 inwhich one of said sprocket wheelsdrives a governor through speed increasingigearing and said governorcontrols said water discharging means.

12; Apparatus as'claimed in claim 1 in; which said counterweight" tankisprovided with transverse. baflies to inhibit longitudinalsurges ofwater therein.

References Cited in'the file of this patent UNITED STATES PATENTS1,487,742 Hill Mar. 25, 1924 2,392,081 Crandall Jan. 1, 1946 FOREIGNPATENTS 365,935 Great Britain Feb. 10, 1932 115,020 Sweden Sept. 18,1945

